Current Electri...

Which of the following statement is false?

In the circuit shown, when R has removed an additional resistance of  $$72\ \Omega $$ must be introduced in series with the battery in order to keep the current through $$30\ \Omega $$ resistance unaltered. Hence R is 

A bar magnet is paced on the axis in a circular coil, close to the coil. Both of them are moved in the same direction. The coil covers $$1\ m$$ in $$0.5 s$$ and the magnet travels, $$2\ m$$ in $$1s$$ then the introduced emf produced in the coil is _______ V.

In the given circuit of potentiometer length of the wire is 6 m then current through the galvanometer when jockey touches the wire at 5.6 m.

The magnitude and direction of current I (in A) indicated in the adjoining circuit is :

Calculate ratio of $${ i }_{ 1 }$$ and $$({ i }_{ 1 }+\quad { i }_{ 2 })$$.

The emf of the battery shown in figure is 

In the given figure if $$i _ { 1 } = 3 \sin \omega t$$ and $$i _ { 2 } = 4 \cos \omega t$$ then $$i _ { 3 }$$ 

A metre bridge cannot be used to determine

Two cells of e.m.f. $${ E }_{ 1  }$$ and $${ E }_{ 2}$$ are joined in series and the balancing length of the potentiometer wire is 625 cm. If the terminals of $${ E }_{ 1}$$ are reversed, the balancing length obtained is 125 cm. Given $${ E }_{ 2}>{ E }_{ 1}$$, the ratio $${ E }_{ 1}:{ E }_{ 2}$$ will be